/Engine/Source/Runtime/Engine/Public/Animation/AnimSubsystem_SharedLinkedAnimLayers.h
Find an existing instance to link given function if one is available, creates one otherwise.
[UAnimInstance](API\Runtime\Engine\Animation\UAnimInstance) * FindOrAddInstanceForLinking ( [UAnimInstance](API\Runtime\Engine\Animation\UAnimInstance) * OwningInstance, [FName](API\Runtime\Core\UObject\FName) Function, bool & IsNewInstance )